Method of recovering ammonia from coal-gases.



F. J. COLLIN.

METHOD 0F RBGOVERING AMMONIA FROM GOAL GASES.

APPLICATION FILED MAB.. 13* 1909. 932,7 58.

Patented Aug. 31. 1909.l

2 SH"ETS-SHEBT l.

I'z gigs! Colli?? I witnesses.

F. J. COLLIN ERING AMMONIA 'FROM COAL GASES. A'BRLIGATION FILED MAB4 13, 1

METHOD 0F REGOV Patented Aug. 31,1909.

2 SHEETS-SHEET 2.

, negled and UNITED s'rnfrns einen@ ennien;4

@muni Joanna mmm,

METHOD QF REUOVERHIG .m FSG @GAL-GASES.

To nii whom 'it may voncem:

it lmnwn @nat I, FRANCIS JOSEPH Son: ein', n subjeet of the Emperor of Ge man?, residing at Dortmnnd, Germany, have in ventisei Gestein new and useui imprese inens in Methods of Recovering Ammonia' frein Unai-Gases, efvwhich the'ieiinwing n prier processes for the recovery si eni- Iienin frein coal-gases, the gases fmmtlne distillationof the coni irsethen Washed with Weten, acids, olsgecini washingsplutions, in scrnbisers, towers, washers 4and'llceapparatus.

'of this-invention is te renover The nbjeet the nmmnnmlby nmorefslmple and economical method lhan herewore, and further- 4steil inside o' the ing the gasinein', from "each oven,

mere to recover n much larger percentage ni' the ammoniecontained in the gases than lieslxeretofore been obtained in practice.

My inventief; .will be understocl 'from the 'following descption, and its scope Wiii be partieularly pointed out in the For the ,purpose of iilust-rating one mi rnngenien efgas pipes, appareils end con neetinnsby Whichmyvinvention may besar-- rie ont, reference may be limi in the se eonxpenying `drawings in Which-- A Figure 1 is en elevation of apparatus an mnged is Carry out my invention, taken en lie line m--w of Fig. 2; 2, is a pian 7View thereof taken on the line zj-Jy of :uni Fig. 3 is an enlarged detail View si' a portion of'snid apparatus. l

VThe ,gases from the cokingelmnilser oi enen even ef e. battery, areiled fiireetiy inte the lettom of 'n collecting gss-mnin 3 through the stand-pipes 2, the elitist each extends above the level ediz. the eentiensntes in tile innin 3. By Ineens of adjnsable bell-covers ii, situs-main, one @ver eeen stand-pipe, end ene -opeieted up end iinwn n level? mechanism inthe nsusi manner, the ,nrnnunt end pressureif the gases enternxny regniatecl or by lowering one ef the beli- Aenvers 4,. the connectien between any ene' coknmcnamber 1andthe collecing gas xfnnin4 3, may be elosed, he condens-etes in the gasfrnnin .acting as a liqnici seni. By, this Ineens- .the heat 'of the entering gsses keeps the eonilensates' i'luicl anni sise ,genervetes vstesm in Some of like effrflensegi Water-'which is sprayer-inver essie heil-sever inereiterA describen# 'Frein the Swinnen i msm wem. Femmes Aug. 31, ieee. Appiicetion e Karen 15%, 19W. ienal Ne. ses,

iiensefl we. is ienee, bythe pum vS'loncl ini@ n. sinsil f5. e 3 near and' persi e "mille gns-eeiieeing mein 3; from this pipe,smell brenda spray this eenden water over @ech eff lie beli-ee'versli in the gasrnein The somewhat eoeleilgases next iern the ierge gss-eellectng. pipethrough pipe 1G inte Watenemlers 11, 1n Whien the' ere further cooled down to about 39 C. r(,860 F.) and a ndensute-oymine/zi, containing prectieeilysll nf thea-1nmenia, bet-31 ,''iee and cnmbme originally containeci. in the gases; this nmxienice-l iiqnni nii e gres ier strength ieeesi in L. seiivoir l?. and from which V1tereefi in; 'the pump '13 intefthenvenhend reservoir ifi. from which ducten iirnngli the nipe i7r connecting the me nf ehe still with tixesatnrater 18 or simiiei nppersns for eombiningthe ammonia wisi. anni er she like. The steam and eilieennmnis-free@ gases next pass inte i? l@ mei from this condenser the conducted-through ipe -.lnis meeting the'gases om ern-er the water-coolers 11.

for inni, pensi.' orilinininating purposes.

To insure uner sli conditions oiweather,

.Lne excess o steam in `the ,gas-main 3,

minnie, s. pipe 2151s provided. bringing stenn inie' the gas main 3 from the'bOilerQZ, m 'which tne comiensatefrem which ammonia has been exiellefl inn of the steam from boiler 22 is used. in stiil i5 sini in inne stiii 16.

L.. am. the nieisture contained in 1 the es fwn nnss direeti'y into n and the'resulting' i hitterl it is f ed intev ine siil l5. intlns still i5, the free amr?" nienin is rives ing steam nionejnnd con in ennyin'g ont this invention, l utilize leaving the water-cmlers,

necessary te this v@recess fer recvery of aen-v l is concentrated; :1. PQr- CJi in such a manner to so thoroughly sa tnrate the gases in the collecting gas-main with' steam, tl'iatpractically allof the free ammo nia is at once combined with the steam and recovered, together vwith `thc combined arnmonia, on subsequently cooling the gases, as an ammonia-cal liquor of greater strength than possible ivlien using existing processes consisting iof lirst cooling the gases Without a prior saturation with steam, and then Washing them in scrnbbers, towers, washers and the like, and in which devices, water, acids or special washing solutions are emp'f'iyed.

.For the purpose ot' utilizing the initial heat contained in the gases, I lead 'the gases into the bottom oi the collecting gas-main through a, vertical stand pipe directly ccnnected with the retorts or ovens, and the outlet of which stand pipe extends slightly above the level of the condensates in the gas-main. the amount and pressure of the gases ent ng the gas-main being regulated by an ad), abre beltcover situated inside ot' the gas-1min, f )perated by a lever mechanism in the usual manner, and capable of forming a. liquid seal it desired. By this means the heat trom the entering gases is transmitted directly to the condensate in the gas-main, and serves to generate steam from the Water therein contained. or from Waterycondensate purposely added, and which steam, mixing with the vases, causes the immediate formation, from the free am- Inonia present, of ammonium hydroxid, and thus prevents the loss of this volatile constituent. To insure the necessary excess v of steam to'fully accomplish this reaction, I

may introduce an additional vquantity of steam which may be derived from a subsequent operation as hereinafter described. New by cooling the gases thus saturated with steam, in any convenient eoolin device down toabout 30 centigrade, I o tain a' condensate ,containing practically all the free ammonia originally contained 4in the gases, as a strong ammonium hydroxid solution, together with an aqueous solution of the fixed ammonium compounds. I-may use a. ortion of thiscondensate for the recovery .0'. further quantities offree ammonia from the vases, and from the balance I drive olf the iree ammonia by subjecting the condensate to 'heat in a suitable apparatus, but I do not, in 'this operation, use any lime or other substance to disassociate the fixed ammo nium compounds also present. The free ammonia thus liberated can be converted into ammonium sulfate or other salt by .vellfknown processes, or condensed by compression into liquid ammonia.

1f there is not enough water in the arry condensate in the gas-main, to generato the maximum amount of steam possible by utilization ot' the heal contained in the entering gases, I may use fresh water or preferably the hot condensate containing the fixed animonia compounds, or the condensate containing free and fixed ammonia can be used.

The surplus condensate containing the fixed ammoniumv compounds may be treated with lime in a" still or other suitable device, and by which treatment .free ammonia is generated and recovered by conversion into ammonium sulfate or other salt by' Well, know-n processes, or condensed by com ression into liquid ammonia. i -Afterthus l1berating the ammonia, this condensateinay be further heated and the steam thus 4generated conducted in part into the'gas-main, and in part used -to drive off the, freel ammonial from the condensate Vwhich hasbeen obtained by cooling the steamsaturated'gases as they come from the `sir-main.

Having now eseribed the ynature of my invention and the manner in which. this new process can behest carried out, claim as my inventionl 1. The method of recovering ammonia from coal-gases, which consists in saturating the hot gases withlstealn immediately upon entering the gas-collecting main, andI then cooling them to recover the contained ammonia.

2. The method of recover-ing ammonia from coal-gases, which consists in leading the gases into a suitable recetacleor gas main in such a manner as to su ject the con; densate in saidga's main to the initial heat of said gases, thereby-converting the Water in the condensate into steam, sat-uniting the gases with steam to combine' With the free ammonia. therein, and then separatingjthe ammoniacal compounds by cooling l In testimonywlieref I affix my signature in presence of two witnesses.

FRANCIS JOSEPH COLLIN. A W itnesses:

Louis VANDORN, Bussm F. Donnie.' 

